Change user creation to not ask for a password (and clarify the readme).

myauth/admin.py

@@ -1,5 +1,16 @@
 from django.contrib import admin
-from django.contrib.auth.admin import UserAdmin
+from django.contrib.auth.admin import UserAdmin as DjangoUserAdmin
 from .models import User
+from .forms import AdminUserCreationForm
+
+
+class UserAdmin(DjangoUserAdmin):
+    add_form = AdminUserCreationForm
+    add_fieldsets = (
+        (None, {
+            'classes': ('wide',),
+            'fields': ('username', ),
+        }),
+    )
 
 admin.site.register(User, UserAdmin)

myauth/forms.py

@@ -0,0 +1,30 @@
+from django import forms
+from django.contrib.auth import get_user_model
+from django.contrib.auth.forms import UsernameField
+
+User = get_user_model()
+
+
+class AdminUserCreationForm(forms.ModelForm):
+    """
+    A form that creates a user, with no privileges, from the given username and
+    password.
+    """
+
+    class Meta:
+        model = User
+        fields = ("username",)
+        field_classes = {'username': UsernameField}
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        if self._meta.model.USERNAME_FIELD in self.fields:
+            self.fields[self._meta.model.USERNAME_FIELD].widget.attrs['autofocus'] = True
+
+    def save(self, commit=True):
+        user = super().save(commit=False)
+        user.set_unusable_password()
+        if commit:
+            user.save()
+        return user
+